The dispute over how Jodi Arias killed her lover came to a head late Thursday when the Arias defense team accused the prosecution’s lead detective of perjury and asked for a mistrial in her murder case.

The motion was denied, but the record was made.

Arias, 30, is on trial in Maricopa County Superior Court in the June 2008 slaying of Travis Alexander, 32, who told his friends that Arias was a stalker but secretly invited her to his Mesa home to have sex.

During one of those trysts, after hours of sex play that reportedly included bondage and explicit photography, Arias shot and stabbed Alexander and nearly cut his head off when she slit his throat.

The Maricopa County Attorney’s Office has charged her with first-degree murder. Arias claims she killed Alexander in self-defense.

The theory of how the killing unfolded, as corroborated by Arias, was fixed for nearly four years.

In 2009, during hearings to determine whether there was probable cause to seek the death penalty against Arias, Detective Esteban Flores told the court that, based on conversations with the county medical examiner and his study of the scene, Arias first shot Alexander.

The shot, it was said, may or may not have knocked him out initially, but ultimately, Alexander then fought with Arias as she stabbed him 27 times and slit his throat.

Flores repeated that theory of the crime in interviews and sworn statements to Arias’ legal team.

But right before the case went to trial, the story changed.

In his opening statements Jan. 2, Deputy County Attorney Juan Martinez told the jury that Arias first stabbed Alexander, then slit his throat and put a bullet in his head after he was already dead.

The difference in the sequence of events could mean the difference between life and death for Arias. If Arias put a bullet in Alexander to finish him off, it could make her self-defense claim less likely. And it would heighten the perception that Arias acted with premeditation instead of the kind of blind rage that could result in a second-degree- murder verdict.

On Tuesday, Medical Examiner Kevin Horn testified that the gunshot likely would have incapacitated Alexander, making it unlikely he fought back. Because Alexander had extensive defensive cuts on his arms and legs, he obviously put up a fight. Therefore, Horn said, it was unlikely he was shot first. And Horn denied ever speaking to Flores about the sequence of wounds.

On Thursday, after hours of testimony about blood spatter and DNA evidence, Arias’ lead defense attorney, Kirk Nurmi, had a chance to grill Flores over the change of facts.

At first, Flores claimed that he didn’t recall whether he heard Horn’s testimony two days earlier. As to his change of opinion of how Alexander died, he said, “That was my understanding at the time. ... I’m not a doctor.”

Over vigorous objections from Martinez, Nurmi pushed the question about Flores’ inaccuracy.

“It was not inaccurate, it was mistaken,” Flores said.

“That’s a pretty big misunderstanding, isn’t it?” Nurmi asked.

“No, I don’t think so,” Flores replied.

Then, when Martinez got his chance to redirect Flores’ testimony, Flores, the lead investigator in the case, stuck to the new version of events and reiterated he had been mistaken in his earlier account.

After the jury was dismissed for the day, Nurmi requested a mistrial, saying that Flores had committed perjury in his testimony.

In open court, Judge Sherry Stephens read aloud the ruling made at the 2009 hearing by Judge Sally Duncan, who was handling the case at the time:

“The State presented evidence that the victim was first shot on the right side of his head near his eye with a .25-caliber handgun and that the bullet lodged in his left cheek. This wound was not fatal and may or may not have rendered the victim unconscious. The victim did not remain unconscious, based on the infliction of the other wounds and the location of blood-spatter evidence in the bathroom sink and blood in the hallway. In addition, the defendant told police that the victim was unconscious after being shot but then crawled around and was stabbed.”

Nurmi pointed out that Martinez had never corrected that “mistaken” version for the record.

But Stephens said that the 2009 ruling was not about the sequence of events, but rather about determining whether there was probable cause to find that the crime was heinous and depraved, thereby qualifying Arias for the death penalty.

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